Here's a good condition 2008 BK Butler Tube Driver Model 911 USA (240V AC) for sale.
 
This the sought after 5 knob custom version.
 
This particular model has the following user controls: " Out Level ", " Hi ", " Lo ", " Tube Drive ", and " Bias ". Round metal click " push-push " button to turn the pedal ON / OFF. " Out "& " In " jacks on the top side panel. The front bottom panel reads: " REAL TUBE OVERDRIVE Concept & Design: BK Butler " in black print.
 
Rear panel is etched both "BK Butler" & "220 ~ 240VAC" . There appears to be an initial of the builder (in black ink) in the interior panel of the unit.
 
Notable users of BK Butler's original hand-made Tube Driver guitar pedals include Eric Johnson, David Gilmour, Billy Gibbons, & Joe Satriani amongst many other professionals.
 
No box included in this sale. Pedal only.
 
Thank you.